Thursday, July 10, 2025

Los Angeles County to Begin Annual Sediment Removal at Devil’s Gate Dam on July 15

County Launches Major Watershed Maintenance Project with Extensive Truck Hauling Plan

Los Angeles County Public Works will begin its annual sediment removal operation on July 15, moving up to 300 trucks daily to transport approximately 100,000 cubic yards of sediment from the Devil’s Gate Reservoir watershed.

The project will run Monday through Friday from 7 a.m. to 4:30 p.m., excluding holidays.

Trucks will follow a designated route west on the 210 Freeway, then via Foothill Boulevard, Osborne Street, Glenoaks Boulevard, and Sheldon Street to Sheldon Pit in Sun Valley.

The maintenance effort stems from a comprehensive restoration project completed in August 2021, which originally removed 1.3 million cubic yards of sediment and restored 70 acres of habitat in the Arroyo Seco Watershed. The annual program aims to maintain flood protection for downstream communities and preserve ecological balance.

“LA County Public Works maintains a sustainable Devil’s Gate Reservoir to provide flood protection to downstream communities while preserving the ecological value of the Hahamongna Watershed,” a County official said.

Most sediment will be transported to Sheldon Pit, with organic debris sent to Scholl Canyon Landfill.

The county said it will continue implementing existing best management practices to ensure public safety and minimize environmental impacts.

Nearly 42 acres within the reservoir will be maintained annually, removing accumulated vegetation and sediment and repairing storm-season erosion.